Oxygenation status of cervical carcinomas before and during spinal anesthesia for application of brachytherapy

To date, no information is available concerning the impact of spinal anesthesia on the oxygenation status of carcinomas of the uterine cervix. The aim of this study was therefore to determine the influence of spinal anesthesia on the oxygenation status of cervical carcinomas.

In ten patients with cervical carcinoma who received spinal anesthesia for a first application of brachytherapy, intratumoral pO2 measurements (pO2 histography system, Eppendorf-Netheler-Hinz, Hamburg, Germany) were performed. Systemic parameters were documented prior to and during spinal anesthesia. Patients breathed room air spontaneously. For further evaluation, all intratumoral pO2 values were pooled, and overall median pO2 values and fractions of hypoxic pO2 values < or = 5 mmHg were calculated. Overall median pO2 values in the subcutis were also calculated.

There were no significant changes of systemic parameters, median subcutaneous pO2 values, median intratumoral pO2 values, and the fractions of hypoxic pO2 values < or = 5 mmHg in the tumor upon administration of spinal anesthesia. The variability of measured pO2 values increased during spinal anesthesia, although substantial changes in the oxygenation status were only seen in individual cases (n = 2).

This study shows for the first time that the oxygenation status of cervical carcinomas, in general, is not influenced by spinal anesthesia prior to application of brachytherapy. To conclude, the data presented suggest that reliable pO2 measurements can be performed under spinal anesthesia. At the same time, since no substantial changes in tumor oxygenation were observed, spinal anesthesia should not affect the O2-related efficacy of high-dose-rate brachytherapy.